Abstract
The transport of heat and charge in the overdoped cuprate superconductor was measured down to low temperature. In the normal state, obtained by applying a magnetic field greater than the upper critical field, the Wiedemann-Franz law is verified to hold perfectly. In the superconducting state, a large residual linear term is observed in the thermal conductivity, in quantitative agreement with BCS theory for a -wave superconductor. This is compelling evidence that the electrons in overdoped cuprates form a Fermi liquid, with no indication of spin-charge separation.
- Received 6 February 2002
DOI:https://doi.org/10.1103/PhysRevLett.89.147003
©2002 American Physical Society